<template>
    <div class="waves-container">
        <svg class="waves" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"
            viewBox="0 24 150 28" preserveAspectRatio="none" shape-rendering="auto">
            <defs>
                <path id="gentle-wave" d="M-160 44c30 0 58-18 88-18s 58 18 88 18 58-18 88-18 58 18 88 18 v44h-352z" />
            </defs>
            <g class="parallax">
                <use xlink:href="#gentle-wave" x="48" y="0" fill="rgba(247,249,252,0.7)" />
                <use xlink:href="#gentle-wave" x="48" y="3" fill="rgba(247,249,252,0.5)" />
                <use xlink:href="#gentle-wave" x="48" y="5" fill="rgba(247,249,252,0.3)" />
                <use xlink:href="#gentle-wave" x="48" y="7" fill="#f7f9fc" />
            </g>
        </svg>
    </div>
</template>

<script>
export default {
    name: "Waves",
};
</script>

<style lang="scss" scoped>
.waves-container {
    width: 100%;
    height: 15vh;
    min-height: 100px;
    max-height: 150px;
    position: absolute;
    bottom: 0;
    left: 0;
    z-index: 1;
    overflow: hidden;
}

.waves {
    position: relative;
    width: 100%;
    height: 15vh;
    margin-bottom: -7px;
    /*Fix for safari gap*/
    min-height: 100px;
    max-height: 150px;
    filter: drop-shadow(0px -2px 2px rgba(0, 0, 0, 0.05));
}

.parallax>use {
    animation: move-forever 25s cubic-bezier(0.55, 0.5, 0.45, 0.5) infinite;
}

.parallax>use:nth-child(1) {
    animation-delay: -2s;
    animation-duration: 7s;
}

.parallax>use:nth-child(2) {
    animation-delay: -3s;
    animation-duration: 10s;
}

.parallax>use:nth-child(3) {
    animation-delay: -4s;
    animation-duration: 13s;
}

.parallax>use:nth-child(4) {
    animation-delay: -5s;
    animation-duration: 20s;
}

@keyframes move-forever {
    0% {
        transform: translate3d(-90px, 0, 0);
    }

    100% {
        transform: translate3d(85px, 0, 0);
    }
}

/*Shrinking for mobile*/
@media (max-width: 768px) {
    .waves-container {
        height: 70px;
        min-height: 70px;
        max-height: 70px;
    }

    .waves {
        height: 70px;
        min-height: 70px;
        max-height: 70px;
        transform: scaleY(1.2);
    }

    .parallax>use {
        animation-duration: 15s;
        /* 减慢动画速度让波浪更明显 */
        animation-timing-function: cubic-bezier(0.5, 0.3, 0.5, 0.7);
    }

    .parallax>use:nth-child(1) {
        animation-duration: 8s;
    }

    .parallax>use:nth-child(2) {
        animation-duration: 11s;
    }

    .parallax>use:nth-child(3) {
        animation-duration: 14s;
    }

    .parallax>use:nth-child(4) {
        animation-duration: 18s;
    }

    @keyframes move-forever {
        0% {
            transform: translate3d(-120px, 0, 0);
        }

        100% {
            transform: translate3d(120px, 0, 0);
        }
    }
}

@media (max-width: 480px) {
    .waves-container {
        height: 60px;
        min-height: 60px;
        max-height: 60px;
    }

    .waves {
        height: 60px;
        min-height: 60px;
        max-height: 60px;
        transform: scaleY(1.3);
    }
}
</style>